Disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) refers to the systemic activation of coagulation mechanisms, leading to the simultaneous formation of intravascular thrombi, secondary hemorrhages due to reactive fibrinolysis, and the consumption of procoagulant factors and platelets. It is always a secondary acquired syndrome that can result from numerous conditions, with a severe prognosis. The diagnosis is based on a set of clinical and biological findings, as no symptom or biological anomaly is pathognomonic or consistent in this condition.

Etiologies

• Severe infections - sepsis = the most common
  • Meningococcus, Salmonella typhi, Pneumococcus, Dengue, Ebola, Marburg, Hanta, EBV, CMV, VZV, HIV, hepatitis, Plasmodium falciparum,…
• Cancers
  • Prostate, breast, ovaries, lungs, intestines, pancreas, acute leukemias, lymphomas,…
• Obstetric pathologies
  • Preeclampsia, eclampsia, HELLP syndrome, placental abruption, amniotic embolism, retained dead fetus, retroplacental hematoma, acute fatty liver of pregnancy, peripartum hemorrhage
• Extensive tissue damage
  • Polytrauma, head trauma, fat embolism, extensive burns, transfusion incompatibilities, pancreatitis
• Liver failure
  • ++ decompensated cirrhosis
• Vascular malformations
  • Giant hemangioma, large vessel aneurysms, hereditary hemorrhagic telangiectasia,
• Envenomations
• Acute intravascular hemolysis
• Miscellaneous
  • Hypothermia, malignant hyperthermia, allergic vasculitis, TTP, HUS, malignant hypertension, congenital protein C or S deficiency, chemotherapy, amphetamines,…

Clinical Presentation

It mainly depends on the nature and severity of the triggering pathology. DIC doubles the risk of death in polytraumatized and septic patients. Main complications:

• Severe hemorrhagic syndrome : purpura fulminans (++ in meningococcal septicemia) with hemorrhagic necrosis and gangrene of the extremities, cerebral-meningeal hemorrhages,…
• Diffuse microthrombosis → multi-system failure : neurological disorders, oliguria, ARDS, pulmonary hypertension, acute limb ischemia,…
• Hyperthermia, hypotension, shock, hemolytic anemia due to microangiopathy (fragmentation of red blood cells in the fibrin network)

Biological Signs

Potential findings:

• Screening tests (= consumption of platelets and coagulation factors) :
  • Thrombocytopenia, decreased plasma fibrinogen, increased APTT and PT, decreased coagulation factors
• Confirmation tests (= fibrinolysis)
  • Increased fibrin and fibrinogen degradation products, increased soluble complexes (thrombin-antithrombin, plasmin-antiplasmin), increased D-dimers
• Other possible abnormalities : schistocytes/ increased Hb/ free bilirubin, increased creatinine (cortical necrosis?), cholestasis or hepatic cytolysis, hypoxia (major lung involvement ?)

Therapeutic Management - Treatments

Intensive care consultation for possible ICU admission and supportive care.

The treatment that most determines the prognosis is primarily etiological!

In all cases, symptomatic management :

• Platelet transfusion (if platelet count < 50,000/ mm³) 1-2 U/10 kg and FFP (if PT < 40%) 15 ml/kg IV. Never use PCC (contains traces of activated factors → risk of worsening coagulopathy)!
• Anticoagulation is debated. Hemorrhagic risk. Use of LMWH (5000-10000 IU/day) in case of thrombotic symptoms with strict monitoring.
• Natural coagulation inhibitor : recombinant activated protein C 24 µg/kg/hour (unless major thrombocytopenia : increased risk of visceral hemorrhage), no indication for antithrombin.
• Fibrinolysis inhibitors have not proven effective. Thrombotic risk. Consider using tranexamic acid or epsilon-aminocaproic acid in severe hemorrhage, under strict monitoring.

Bibliography

Longo DL et al., Harrison - Principes de médecine interne, 18e éd., Lavoisier, 2013

Leung LLK, Evaluation and management of disseminated intravascular coagulation (DIC) in adults, UpToDate, 2024